The biggest quake was a notable 4.2-magnitude shaker just after 7 a.m. amid an hour-long swarm that began with a ...

The West Coast of North America is a geologically tumultuous zone where tectonic plates collide, subducting under and scraping past one another. Over the eons, this activity has regularly caused major ...

Three huge tectonic plates meet at the Mendocino triple junction off the coast of northern California, and a new study ...